RJM Performance Clutch Pedal Assembly
#91
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For my own curiosity, it will be interesting to get in & out of two 6MT G's with the two different clutch pedals, for an immediate comparison. I'm sure it will contribute to the overall analysis. It's one thing to describe the differences based on memory, but quite another to experience them as an immediate side-by-side compare.
#92
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Installed last night, driven a fair amount. Another bit of driving today. And now this review.
INSTALLATION
I did not do the installation myself. My buddy Matt did the install, and he wasn’t intimidated at all by the process. We didn’t even remove the driver’s seat, although we were planning on it. Start to finish, it took maybe 1.5 hours. There was a little bit of confusion about the RJM spring and how it’s properly seated. And it took a while to realize it’s possible to over-tighten the assembly, so that the bushings don’t move freely enough for the pedal to return to position with appropriate force. And then there was about an hour of driving around, testing where the three of us liked the dial position best.
We installed the clutch pedal flush with the brake pedal, although it could be adjusted in or out further. I figured even with the brake was fine. Truth is, I didn’t take note where the OEM pedal location was in relation to the brake pedal. If someone wants to comment on that, have at it.
MOVEMENT
The effort required to push the pedal down, and the feel of the pedal on the way up, is now extremely linear. Whereas the necessary force applied to the OEM pedal is very decidedly a curve. Comparing the two experiences, the RJM pedal has a more natural feel. To me, this is a good thing.
Because of this linear movement, you don’t have to *roll* your foot over the pedal in order to engage it properly. I don’t know how else to explain this. Now you just push it in and out, without the need for extra finesse. On the one hand: OMG thank you! On the other hand… there is a weird sense of pride thinking it takes skills to drive Nissan’s 6MT in the G/Z. And while that may be true for some, it’s more a factor of a poorly designed clutch pedal than it is an actual driving challenge to overcome.
BTW, the pedal also has more vibration now. You can feel things through your foot that are typically masked by the OEM pedal. To me, this is also a good thing. To auto designers of mass-produced sedans, probably not so much.
ENGAGEMENT
My friends and I discussed this at length, and all agreed on the following diagram. [edit] I've since discussed this interpretation with Ryan at RJM Performance, and he confirmed relative accuracy to this graphic. Go figure
Essentially, the effective area of engagement has been moved down the pedal throw, and the adjustment **** allows you to adjust the width of that area. Dial the **** all the way clockwise, and you get pretty close to OEM engagement. Dial the **** all the way counter-clockwise, and you widen the effective area quite a bit. Either way, the effective area is now further down the clutch pedal travel than it was OEM.
Personally, I prefer the wider engagement. I think other people do, too. So I dial the **** all the way counter-clockwise, then a full turn back the other way. It might help to use your free hand to pull up on the pedal when turning the ****.
DRIVING
No matter how skilled you think you are with the OEM clutch pedal, there will come a time when you accidentally stall the car. Just admit it, LOL. No one is perfect. However, with this new pedal that will never happen again. Guaranteed.
You know how difficult it is to get a smooth roll out of the hole? Even harder if you’re trying to launch out of the hole? Well, those days are gone. The car is so-o-o-o-o much more easy to drive now, and shifts are like butter, particularly the lower gears 1-2-3.
FINAL ANALYSIS
Should have bought this sooner. I’ve had this car for 3.5 years now, and all along I kept saying jsolo’s return spring was good enough. Why perform elective surgery when all you need is a band-aid, right? Wrong. This mod is only $250 if you or a friend installs it for the cost of beer and a steak dinner. And it’s worth every penny.
Add my voice to the chorus of positive reviews.
INSTALLATION
I did not do the installation myself. My buddy Matt did the install, and he wasn’t intimidated at all by the process. We didn’t even remove the driver’s seat, although we were planning on it. Start to finish, it took maybe 1.5 hours. There was a little bit of confusion about the RJM spring and how it’s properly seated. And it took a while to realize it’s possible to over-tighten the assembly, so that the bushings don’t move freely enough for the pedal to return to position with appropriate force. And then there was about an hour of driving around, testing where the three of us liked the dial position best.
We installed the clutch pedal flush with the brake pedal, although it could be adjusted in or out further. I figured even with the brake was fine. Truth is, I didn’t take note where the OEM pedal location was in relation to the brake pedal. If someone wants to comment on that, have at it.
MOVEMENT
The effort required to push the pedal down, and the feel of the pedal on the way up, is now extremely linear. Whereas the necessary force applied to the OEM pedal is very decidedly a curve. Comparing the two experiences, the RJM pedal has a more natural feel. To me, this is a good thing.
Because of this linear movement, you don’t have to *roll* your foot over the pedal in order to engage it properly. I don’t know how else to explain this. Now you just push it in and out, without the need for extra finesse. On the one hand: OMG thank you! On the other hand… there is a weird sense of pride thinking it takes skills to drive Nissan’s 6MT in the G/Z. And while that may be true for some, it’s more a factor of a poorly designed clutch pedal than it is an actual driving challenge to overcome.
BTW, the pedal also has more vibration now. You can feel things through your foot that are typically masked by the OEM pedal. To me, this is also a good thing. To auto designers of mass-produced sedans, probably not so much.
ENGAGEMENT
My friends and I discussed this at length, and all agreed on the following diagram. [edit] I've since discussed this interpretation with Ryan at RJM Performance, and he confirmed relative accuracy to this graphic. Go figure
Essentially, the effective area of engagement has been moved down the pedal throw, and the adjustment **** allows you to adjust the width of that area. Dial the **** all the way clockwise, and you get pretty close to OEM engagement. Dial the **** all the way counter-clockwise, and you widen the effective area quite a bit. Either way, the effective area is now further down the clutch pedal travel than it was OEM.
Personally, I prefer the wider engagement. I think other people do, too. So I dial the **** all the way counter-clockwise, then a full turn back the other way. It might help to use your free hand to pull up on the pedal when turning the ****.
DRIVING
No matter how skilled you think you are with the OEM clutch pedal, there will come a time when you accidentally stall the car. Just admit it, LOL. No one is perfect. However, with this new pedal that will never happen again. Guaranteed.
You know how difficult it is to get a smooth roll out of the hole? Even harder if you’re trying to launch out of the hole? Well, those days are gone. The car is so-o-o-o-o much more easy to drive now, and shifts are like butter, particularly the lower gears 1-2-3.
FINAL ANALYSIS
Should have bought this sooner. I’ve had this car for 3.5 years now, and all along I kept saying jsolo’s return spring was good enough. Why perform elective surgery when all you need is a band-aid, right? Wrong. This mod is only $250 if you or a friend installs it for the cost of beer and a steak dinner. And it’s worth every penny.
Add my voice to the chorus of positive reviews.
#93
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iTrader: (5)
Well I just bought one. After driving the car around today and complaining further about the OEM clutch pedal, I realized that I'd rather give it a try than wait to test out someone else's car and then realize I'm an idiot for not doing this sooner. Will hopefully have this installed before the meet in 2 weeks.
#94
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Well I just bought one. After driving the car around today and complaining further about the OEM clutch pedal, I realized that I'd rather give it a try than wait to test out someone else's car and then realize I'm an idiot for not doing this sooner. Will hopefully have this installed before the meet in 2 weeks.
I promise, you'll have zero regrets, buddy. Unless you whack the installation and start throwing wrenches at your car. That would be bad.
#95
Premier Member
iTrader: (5)
RJM Performance Clutch Pedal Assembly
It is going to be a tight stretch. I wasn't aware these ship from Canada as I received the notice today stating my kit is being produced and will ship on Wednesday morning. Regardless I couldn't install until next week. Once I have the components, I'll be able to see if it's something I want to tackle in the garage, or get to a shop to install.
#96
is this pedal assembly able to fully depress the CMC at any adjustment?
I get a little worried about the pedal height for clutch engagement over the life of the clutch.
Traditionally, as a clutch wears, the clutch pedal engagement point lowers. This would make sense because the CSC has to push further to disengage a thinner clutch.
However, the engagement point is already quite low with this pedal assembly.
Would anybody have any diagrams or videos of the piece in operation?
I'm sure such a trivial problem has been considered and engineered for. Would just want to see the validation before possible purchase.
Thanks in advance!
I get a little worried about the pedal height for clutch engagement over the life of the clutch.
Traditionally, as a clutch wears, the clutch pedal engagement point lowers. This would make sense because the CSC has to push further to disengage a thinner clutch.
However, the engagement point is already quite low with this pedal assembly.
Would anybody have any diagrams or videos of the piece in operation?
I'm sure such a trivial problem has been considered and engineered for. Would just want to see the validation before possible purchase.
Thanks in advance!
#97
Just say no!!!!!
iTrader: (14)
I believe you'll get the most pedal stroke with 0% afp (adjustment **** turned all the way in). This is still not entirely the same as stock pedal stroke.
That said, MC stroke can always be adjusted with the MC rod that connects to the pedal. You would extend it (screw it out away from the clevis fork) to gain more MC piston stroke. This will also make the grab point higher off the floor.
That said, MC stroke can always be adjusted with the MC rod that connects to the pedal. You would extend it (screw it out away from the clevis fork) to gain more MC piston stroke. This will also make the grab point higher off the floor.
#98
Yup, totally understood. So that would lead one to believe that when adjusted such that engagement point is closer to the floor, the CSC is not getting full extension.
Surely that's not the case though, and I am looking for validation of such. (non-full extension would count as a poorly adjusted clutch in my book).
Surely that's not the case though, and I am looking for validation of such. (non-full extension would count as a poorly adjusted clutch in my book).
#99
Just say no!!!!!
iTrader: (14)
Yup, totally understood. So that would lead one to believe that when adjusted such that engagement point is closer to the floor, the CSC is not getting full extension.
After rjm adjustment, you now have exactly 6mm of CSC travel, enough for full clutch disengagement and pedal uptake much closer to the floor.
The point is, it's not necessary to have full extension of either component (MC or SC) for proper operation. What is important is that the clutch does fully disengage with the pedal to the floor, and fully engage with the pedal at the top (off the floor) position.
Re-examining your original question, the friction disk is sandwiched between the pressure plate and flywheel. The latter is fixed. Only the pressure plate actually has lateral movement. As the friction disc wears, pressure plate has to move further in to compensate. Question is, what happens to the fingers that the throwout bearing engages. As I understand it when a new clutch is installed, there no gap between the fingers and throwout bearing. What happens as the friction disc wears....?
Edit: There are some pressure plate designs that compensate for disc wear and retain the original 'finger' position. I don't know if nissan's design is as such.
Last edited by JSolo; 08-19-2015 at 12:55 AM.
#100
Originally Posted by Mike Kojima on 370.zom
The stock 370Z pressure plate on the left has an unusual self adjusting feature. The diaphragm spring is pulled up the ratchet like ramps stamped into the cover by the springs on the top of the cover. You can see the ramps here. This keeps the freeplay from the pressure ring to the clutch disc constant as the disc wears, keeping the clamping load from decreasing with time. The JWT pressure plate on right is a conventional heavy duty part...
#102
I don't believe this is true, Jsolo. The stock pressure plate allows for the same window of engagement throughout its life. The aftermarket pp without the "ramped fingers" would not need pedal adjustment for effective engagement. It would only shift the window and length of engagement(no mechanical compromise over stock). I believe this is a negligible shift for most drivers. Even enthusiasts. The transition period of wear is so lengthy, the driver typically doesn't notice with quality parts.
#104
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#105
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After putting Rochester's car in reverse then, pulling out of a parking spot in 1st gear (which is all that it took) LOL, I'm going to work on the install today.
I've reviewed the instructions a few times over and have a much better idea of the install process. Will report back later once I'm done cursing from the awkward location and driving around to get the proper AFP dialed in.
I've reviewed the instructions a few times over and have a much better idea of the install process. Will report back later once I'm done cursing from the awkward location and driving around to get the proper AFP dialed in.